This invention relates to a pacifier for undersized newborn babies and, in particular, for premature or undersized newborns having a birthweight under approximately five pounds.
Several pacifiers in the prior art are designed for use by full-term newborn babies, or newborns that are of normal size having a birthweight of over five pounds. To our knowledge, there has been no pacifier as yet that is specifically sized and shaped to meet the needs of the premature or small full-term infant. Pacifiers of the prior art for newborns, such as that described in U.S. Pat. No. 4,321,927, have been concerned primarily with providing a pacifier having a safety shield or mouth shell that prevents the baby from swallowing the pacifier, while preventing the safety shield from blocking the nasal passages of the newborn.
Babies born early frequently do not have fully developed or coordinated sucking and swallowing reflexes, particularly newborns of 32 to 35 weeks gestation. In addition, some premature newborns, and small full-term babies (under approximately five pounds in birth weight), may have a much smaller intraoral cavity than the average full-term baby. Since premature infants may have underdeveloped intraoral cavities and may demonstrate incoordinate sucking patterns, use of conventional nipples and pacifiers are inappropriate to facilitate improvement in sucking responses in these infants. Babies with poorly coordinated sucking abilities are at risk during oral feeding of regurgitating and aspirating the formula. Moreover, this poor coordination and weakness in sucking frequently means that the newborn will be unable to obtain the amount of formula needed for normal growth, without expending excessive energy in sucking.
Premature or small infants often require gavage feedings in order to obtain proper nourishment. Non-nutritive sucking opportunities available for babies fed through nasogastric (NG) tubes are generally inadequate and unsafe, which retards the development of normal, healthy sucking capabilities. Frequently, therapists or nurses work with NG tube babies using their fingers as a sucking stimulus. Premature infants unable to suck during gavage feeding often do not associate sucking with nourishment, which further retards the newborn's transition to oral feeding. To our knowledge, no commercially available pacifier is adapted for use according to recommended standards in conjunction with nasogastric tubes.
Research has demonstrated that pacifier use during nasogastric feedings in premature infants accelerates the maturation of the sucking reflex. See, e.g., Bernbaum, Pereira, Watkins and Peckham, "Nonnutritive Sucking During Gavage Feeding Enhances Growth and Maturation in Premature Infants", Pediatrics, pp. 41-45, Vol. 71, No. 1, 1983, and Measel and Anderson, "Nonnutritive Sucking During Tube Feedings: Effect on Clinical Course in Premature Infants", JOGN Nursing, pp. 265-272, Sept./Oct. 1979, both references of which are incorporated herein by reference.
Standard sized nipples or pacifiers have been found to be too large for the premature newborn, causing the infant to gag or to push the nipple out. One method of overcoming this problem has been to use the bulb end of a typical disposable medicine dropper as a nipple substitute. However, the medicine dropper bulb is not designed specifically for an infant's intraoral cavity. To our knowledge, no prior art pacifier is available that is directly compatible with the small intraoral cavity of a premature or small newborn and that is sized and shaped to stimulate the sucking response of the baby without irritating or sensitizing the infant's perioral or intraoral regions.
Under normal circumstances, a baby's tongue puts pressure on the roof of the mouth and on the palatal arches during normal sucking. But when a normal sucking response has not yet developed, such as in undersized babies, the tongue surface, palate, or arches may become hypersensitive because they have never received adequate pressure from the infant's tongue. This hypersensitivity may produce an increased gag reflex. On the other hand, in NG tube babies, the NG tube is constantly pressing on the back of the soft palate, which can result in a reduced gag reflex. In either case, it is critical that the nipple of the pacifier be sized and shaped to fill the oral cavity appropriately without undue pressure in some regions and inadequate pressure in others.
A pacifier, such as that sold under the tradename "NUK", is presently available for normal sized babies that has a bulbous nipple with a flattened surface, such as is illustrated in the patent to Frodrich et al., U.S. Pat. No. 4,078,570. The flattened surface on the "NUK" nipple is oriented at an acute angle to the axis of the nipple and is, therefore, adapted for use by a baby with a normal degree of developmental sucking ability. Normal newborns elevate the back of their tongue as they swallow after a suck. Some premature infants with weak, incoordinate sucks have not yet developed the ability to elevate the tongue in the posterior dorsal tongue surface. While standard pacifiers generate pressure on the dorsal tongue surface of a normal infant during sucking, these pacifiers fail to provide the same pressure and stimulus for some special newborns.
It is known that a natural, physiological stimulus that is designed to simulate the perioral pressure experienced by a baby during breast feeding can enhance the feeding response. See, e.g., Rogers RC et al., "Afferent Projections to the Dorsal Motor Nucleus of the Vagus", Brain Research Bulletin 5:365-373, 1980. Perioral pressure stimulates pressure receptors located in the skin around the infant's mouth. Upon stimulation, these receptors send signals to the brain, resulting in an activation of the parasympathetic division of the autonomic nervous system. The parasympathetic division functions to restore energy to the baby, such as during feeding and sleeping.
Accordingly, it is an object of the present invention to provide a pacifier for premature or small newborn infants. Another object is to provide a pacifier that will enhance the sucking response of the newborn while preventing the development of hypersensitivity in the perioral and intraoral regions of the infant. Further objects and advantages of the present invention will be more clearly demonstrated in the following description of the invention and accompanying figures.